1651838891 has 6 divisors (see below), whose sum is σ = 1743353892. Its totient is φ = 1564899660.

The previous prime is 1651838857. The next prime is 1651838921. The reversal of 1651838891 is 1988381561.

It is not a de Polignac number, because 1651838891 - 2¹⁰ = 1651837867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1651838191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2287505 + ... + 2288226.

It is an arithmetic number, because the mean of its divisors is an integer number (290558982).

Almost surely, 2^1651838891 is an apocalyptic number.

1651838891 is a deficient number, since it is larger than the sum of its proper divisors (91515001).

1651838891 is an equidigital number, since it uses as much as digits as its factorization.

1651838891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4575769 (or 4575750 counting only the distinct ones).

The product of its digits is 414720, while the sum is 50.

The square root of 1651838891 is about 40642.8209035741. The cubic root of 1651838891 is about 1182.1045681999.

The spelling of 1651838891 in words is "one billion, six hundred fifty-one million, eight hundred thirty-eight thousand, eight hundred ninety-one".